Hortscience最新文献

{"title":"Retractable Netting and Evaporative Cooling for Sunburn Control and Increasing Red Color for ‘Honeycrisp’ Apple","authors":"Noah Willsea, Victor Blanco, Orlando Howe, Thiago Campbell, Erica Casagrande Biasuz, Lee Kalcsits","doi":"10.21273/hortsci17339-23","DOIUrl":"https://doi.org/10.21273/hortsci17339-23","url":null,"abstract":"Protective netting and evaporative cooling are commonly used for sunburn protection in apple ( Malus domestica Borkh.) orchards in semiarid environments such as central Washington state. Sunburn is caused by a combination of solar radiation and heat, which can cause significant economic losses. Although protective netting and evaporative cooling can be effective for preventing apple sunburn, netting can also introduce new risks, including red color development on the fruit surface. This study evaluated whether retracting netting before harvest improves red color development and/or changes sunburn risk compared with leaving netting in place until after harvest. An experiment was conducted that compared three netting treatments: 1) netting from June until harvest, 2) netting retracted 10 d before harvest, and 3) no netting all season combined with the presence or absence of evaporative cooling. Fruit was harvested and assessed for sunburn incidence and external quality characteristics immediately after harvest. In retracted netting treatments, red color was higher when netting was retracted compared with the nonretracted controls, and sunburn risk did not increase with netting retraction. Evaporative cooling reduced sunburn incidence. Retractable netting can be used to minimize the loss of fruit to sunburn while allowing a full light environment that promotes red color near harvest. There is no inherent increase in sunburn risk from netting retraction, and the proportion of fruit with red color improved.","PeriodicalId":13140,"journal":{"name":"Hortscience","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135012573","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling Northern Highbush Blueberry Cold Hardiness for the Pacific Northwest","authors":"Clark Kogan, Lisa W. DeVetter, Gwen-Alyn Hoheisel","doi":"10.21273/hortsci17320-23","DOIUrl":"https://doi.org/10.21273/hortsci17320-23","url":null,"abstract":"Freezing temperatures in fall, winter, and spring can cause damage to multiple perennial fruit crops including northern highbush blueberry ( Vaccinium corymbosum ). Predictive modeling for lethal temperatures allows producers to make informed decisions about freeze mitigation practices but is lacking for northern highbush blueberry grown in the Pacific Northwest. If buds are hardier than air temperatures, unnecessary use of propane heaters and/or wind machines is costly. In contrast, use of heaters and/or wind machines during freezing, damaging temperatures can minimize crop damage and potential yield loss. The objective of this study was to model cold hardiness across multiple cultivars of northern highbush blueberry grown in various regions in Washington, USA, and to generate predictive cold hardiness models that producers in the Pacific Northwest could use to inform freeze mitigation. Multiple years of experimental cold hardiness data were collected on four cultivars of northern highbush blueberry grown in western and eastern Washington, USA. Freeze chambers were used to reduce bud temperatures systematically, after which buds were dissected and bud survival was assessed. A generalized linear mixed model with a binomial response and logit link was fit to each cultivar to characterize the relationship between bud survival, freezer temperature, recent air temperatures, and growing degree days from fall acclimation to late winter/spring deacclimation. Model simulation was performed to obtain marginal-scale lethal temperature estimates. Model error estimation was performed using cross validation. Results show cultivar-specific cold hardiness models can be generated, and model development and use can help growers make more informed decisions regarding freeze protection that also minimizes costly applications of freeze protection when unnecessary. Furthermore, such models can be adapted to other blueberry growing regions and cultivars experiencing similar climactic conditions.","PeriodicalId":13140,"journal":{"name":"Hortscience","volume":"765 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135012000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microbial Community Structure in Soilless Substrates Used for Nursery Crops","authors":"Silvia Valles-Ramirez, James E. Altland, Anna L. Testen, Jelmer W. Poelstra, Frederick C. Michel","doi":"10.21273/hortsci17275-23","DOIUrl":"https://doi.org/10.21273/hortsci17275-23","url":null,"abstract":"Soilless substrates are widely used for plant cultivation. However, little is known about how soilless substrate components, plant growth, or their interactions impact microbial communities in soilless media. The objectives of this study were to analyze microbial communities in typical pine bark substrates used for nursery crop production and determine the impacts of substituting peat with a compost substrate, and planting, on microbial community dynamics over a production cycle. Three soilless substrate mixtures were compared. The substrate mixes consisted of 80:20:0, 80:10:10, and 80:0:20 (volume:volume:volume) ratios of pine bark:peatmoss:leaf compost, respectively. One set of each treatment was planted with a single birch ( Betula nigra ‘Cully’) liner and another set was not planted. The treatments (n = 3) were maintained in a nursery production setting, and samples were taken after 0, 1, 2, 3, and 4 months. Bacterial and fungal communities were characterized by sequencing polymerase chain reaction-amplified 16s rRNA genes and internal transcribed spacer regions. Initially, the two substrate mixtures that contained compost had more phyla than the substrate mixture that only contained peat and bark. After 1 month, microbial communities in all treatments contained similar phyla, but at different relative abundances based on the amount of compost they contained. Over time, Nitrosomonadaceae and Acetobacteraceae were the most abundant bacterial families in substrate mixes containing 10% and 20% compost, but they were absent from treatments without compost. The communities were dynamic and changed the most over the first 2 months. Microbial communities and their dynamics were similar between planted and unplanted treatments. Planting had less of an effect on microbial communities than compost amendment. Among the fungal communities, differences were observed based on both compost amendment and plant presence. Ascomycota and Basidiomycota were the most abundant fungal phyla and resembled those originally in the peat and compost, respectively. These findings could be used to understand the importance and dynamics of specific microbial communities present in substrate components and how they develop during greenhouse production.","PeriodicalId":13140,"journal":{"name":"Hortscience","volume":"62 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135012571","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Aminoethoxyvinylglycine Reduces Preharvest Fruit Drop and Fruit Ethylene Evolution in ‘Red Delicious’ Apple but Affects Fruit Size and Quality Inconsistently","authors":"Anish Malladi, Krittika V. Tonapi, Thomas M. Kon","doi":"10.21273/hortsci17287-23","DOIUrl":"https://doi.org/10.21273/hortsci17287-23","url":null,"abstract":"Aminoethoxyvinylglycine (AVG) is widely used in commercial apple ( Malus × domestica Borkh.) production to reduce preharvest fruit drop (PFD) and delay ripening for harvest management. Recently, the maximum allowable concentration of AVG was doubled (up to 264 mg⋅L −1 ). Reports of the relationship between the AVG concentration and fruit growth, size, and quality have been contradictory. We evaluated the relationship between the AVG concentration and PFD, fruit size, fruit quality, and expression of ethylene signaling-related and cell wall modification-related genes. Experiments were conducted in 2019 and 2020 using mature ‘Red Delicious’ in western North Carolina. The AVG treatments [0 and 132 (AVG-1x) and 264 mg⋅L −1 (AVG-2x)] were applied 3 weeks before the expected harvest. The AVG treatments reduced fruit drop and internal ethylene concentration relative to the control in both years. There was no difference in drop between AVG-1x and AVG-2x applications. Only in 2020 did AVG treatments delay fruit softening and starch hydrolysis and reduce soluble solids concentration. There were no effects on red fruit color development. Fruit size was unaffected by AVG in 2019, but it was reduced in 2020 with the AVG-2x application. AVG reduced ethylene synthesis and altered signaling, evidenced by decreased relative expression of genes related to ethylene signaling ( ARGOS1, ARGOS2 ). AVG applications also reduced the expression of EXPA8;1 , suggesting that reduced cell wall disassembly was associated with a reduction in fruit softening. These results indicate that preharvest applications of 132 mg⋅L −1 AVG effectively reduced PFD via altering ethylene evolution and signaling. Use of a higher AVG concentration was of limited benefit.","PeriodicalId":13140,"journal":{"name":"Hortscience","volume":"228 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135112525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Raising Mowing Height Improves Freeze Tolerance of Putting Green–type Bermudagrass","authors":"Mingying Xiang, Shuhao Yu, Lakshmy Gopinath, Hassan Salahi, Justin Q. Moss, Yanqi Wu","doi":"10.21273/hortsci17351-23","DOIUrl":"https://doi.org/10.21273/hortsci17351-23","url":null,"abstract":"There is a growing trend of cultivating hybrid bermudagrass [ Cynodon dactylon (L.) Pers. × Cynodon transvaalensis Burtt-Davy] on golf course putting greens in the transition zone because of its excellent quality in the summer months, coupled with less pesticide input than creeping bentgrass ( Agrostis stolonifera L.). However, the long-term success of bermudagrass putting greens is hindered by low temperatures in winter months, particularly in the transition zone. To address this issue, in addition to genetic improvement for cold hardiness through the development of new cultivars, effective management approaches are necessary to enhance the winter survival of putting green–type bermudagrass. The objective of this study was to investigate the relative freeze tolerance of four bermudagrasses and the effects of raising mowing height on the freeze tolerance of putting green–type bermudagrasses. In this study, two experimental putting green–type bermudagrasses (11X2 and OKC0805) along with cultivars TifEagle and OKC3920 were tested at two mowing heights (3.2 vs. 6.4 mm) at freeze temperatures that ranged between –4 and –11 °C. The lethal temperature to kill 50% of the population (LT 50 ) as well as regrowth vigor during recovery were evaluated. Variety ‘OKC3920’ demonstrated enhanced freeze tolerance compared with ‘TifEagle’ at both mowing heights. Increasing the mowing height from 3.2 mm to 6.4 mm improved freeze tolerance for most genotypes tested in this study. After exposing the grasses to –8 °C for 1 hour, genotypes such as 11X2 exhibited better regrowth vigor and demonstrated a faster recovery. This study suggests that golf course managers can enhance winter resilience of bermudagrass putting greens by selecting genotypes strategically with superior freeze tolerance and raising mowing heights in the fall acclimation process.","PeriodicalId":13140,"journal":{"name":"Hortscience","volume":"45 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136371669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Simulated Photovoltaic Roofs on the Yield and Nitrate Content of Pak Choi and Rape","authors":"Chiao-Ling Hsiao, Ching-Yuh Wang, Yi-Ting Hsu","doi":"10.21273/hortsci17240-23","DOIUrl":"https://doi.org/10.21273/hortsci17240-23","url":null,"abstract":"Integrating solar modules into agricultural production constitutes a novel type of agricultural industry. We evaluated the effect of setting opaque plastic solar modules on greenhouse roofs on the crop growth inside greenhouse. The opaque plastic agricultural films simulating the material of solar modules and the greenhouse roofs covered with these films were used, and the yield and nitrate content of pak choi ( Brassica chinensis ‘Bekamaru’) and rape ( Brassica napus ‘Dragon’) under these films were measured. The results indicated that the yield of pak choi did not change considerably by a simulated photovoltaic (SPV) roof with a shading rate of 38% compared with an uncovered plastic (PL) roof. However, during the first and second planting periods, the yield of rape under the PL roof substantially exceeded that under the SPV roof by 31% and 34%, respectively, indicating that the effect of shading on the yield of rape was greater than that on the yield of pak choi. In addition, the appearance of pak choi and rape also changed under the SPV roof, such as fewer leaves, lower chlorophyll content, and larger specific leaf areas. Nevertheless, the nitrate content of crops grown under the SPV roof exceeded that of crops grown under the PL roof. In conclusion, based on the expression of yield and growth of crops, pak choi is suitable for cultivation in greenhouses that are equipped with photovoltaic systems. However, to prevent plants from accumulating excessive nitrate, attention must be focused on the amount and frequency of nitrogen fertilizers application.","PeriodicalId":13140,"journal":{"name":"Hortscience","volume":"28 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136371860","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Risk Management Training Program Designed to Empower Urban Women Farmers","authors":"Robin G. Brumfield, Deborah Greenwood, Madeline Flahive DiNardo, Arend-Jan Both, Joseph R. Heckman, Ramu Govindasamy, Nicholas Polanin, Ashaki A. Rouff, Amy Rowe, Richard VanVranken, Surendran Arumugam","doi":"10.21273/hortsci17305-23","DOIUrl":"https://doi.org/10.21273/hortsci17305-23","url":null,"abstract":"Annie’s Project: Farming in New Jersey’s Cities and the Urban Fringe focused on the following five areas of risk identified by the US Department of Agriculture Economic Research Service: financial, production, marketing/price, legal/institutional, and human/personnel. Additional education regarding urban farming topics included securing suitable land, dealing with contaminated soils and alternative growing medias, and securing water for crop production. We delivered a series of six 3-hour evening classes to 23 producers. We administered a retrospective evaluation at the conclusion of the series and distributed an evaluation survey 6 months after training. Both evaluations found that participants increased their understanding of farm risks. Furthermore, they indicated they were better able to manage the impacts of the COVID-19 pandemic on their farm business activities.","PeriodicalId":13140,"journal":{"name":"Hortscience","volume":"28 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136371861","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dissolution of Silicon from Soilless Substrates and Additives","authors":"Mackenzie G. Dey, Jennifer K. Boldt, Bruce Bugbee","doi":"10.21273/hortsci17189-23","DOIUrl":"https://doi.org/10.21273/hortsci17189-23","url":null,"abstract":"Silicon (Si) is a beneficial element that is usually ample in mineral soil solution, but it is minimally bioavailable from soilless substrates. Several Si additives are commercially available, but the rate of dissolution of Si is not well-characterized. The ideal additive would steadily release bioavailable Si over the crop lifecycle. We report the long-term (120 days) dissolution of Si from soilless substrates and substrate additives. Studies involving gently agitated containers with deionized water indicated that perlite, sphagnum peat, vermiculite, and coconut coir released less than 0.03 mmol Si per liter of substrate per day. Rice hulls and wollastonite (CaSiO 3 ) had 7- to 130-times faster rates of dissolution in this system; therefore, they were further studied in peat-based media. Dissolution of Si from the addition of 1 g wollastonite per liter of peat peaked at day 10 at 2.1 mmol Si per liter of media per leaching event (15% by volume); then, it gradually decreased over 120 days. The peak dissolution of Si amended with 12% rice hulls was similar, but it gradually increased over time. The concentrations of nine heavy metals in plant tissue were compared with untreated control plants to determine wollastonite and steel slag. The concentration of some elements statistically increased, but all concentrations were well below the legal concentration limits of these elements for human consumption in the United States. These results indicate that both wollastonite and rice hulls steadily release Si for up to 4 months; therefore, they are good sources of Si for container-grown crops in soilless media.","PeriodicalId":13140,"journal":{"name":"Hortscience","volume":"26 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136371865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluating Various Colors of Persistent Luminescent Powders on Rose Cut Flowers","authors":"Abby Pace, Bruce L. Dunn, Charles Fontanier","doi":"10.21273/hortsci17282-23","DOIUrl":"https://doi.org/10.21273/hortsci17282-23","url":null,"abstract":"Rose cut flowers are popular in everyday bouquets or for special occasions, and tinting of the flowers by means of color addition increases the flowers economical value and aesthetic appeal. This study evaluated red and white luminescent rose cut flowers, which was achieved by applying six persistent luminescent powders. Solutions of each color were prepared by mixing 6 g of powder and 240 ml of deionized water and sprayed four times around the flower head plus a control. Images were taken of the flowers before ultraviolet blacklight exposure and after exposure to be later analyzed with ImageJ software. Daily measurements were taken including vase weight, average floral diameter, and visual deterioration based on scale of 1 to 4. Overall measurements included mean brightness; red, green, and blue measured values; dominant wavelengths of emitted color; flower diameter change rate; relative water percent; solution uptake rate; and vase solution uptake rate. For luminescent brightness mean without ultraviolet, white rose with blue powder had the greatest value. For luminescent brightness after ultraviolet exposure, white rose with green powder had the greatest value. With ultraviolet exposure, white roses with green powder had the greatest value followed by blue, orange, and white. Red powder on white and red roses experienced little to no luminescence before or after ultraviolet exposure. Mean and mode varied in their calculated dominant wavelengths; therefore, it is recommended to use mean values because more similarities in matching of the powder color and the calculated dominant wavelength were reported. Ultimately, white roses are preferred because they seemed to have greater health and luminescence compared with red roses, and green and blue powder would be recommended for luminescent application for brightness.","PeriodicalId":13140,"journal":{"name":"Hortscience","volume":"228 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135112524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bloom and Postbloom Thinner Effects and Interactions on ‘Gala’ Fruit Growth Rate, Return Bloom, and Yield Responses at Three Locations","authors":"James E. Larson, Duane W. Greene, James R. Schupp, Christopher D. Clavet, Thomas M. Kon","doi":"10.21273/hortsci17353-23","DOIUrl":"https://doi.org/10.21273/hortsci17353-23","url":null,"abstract":"Multistep chemical thinning programs have been widely recommended in the eastern United States; however, adoption of bloom thinners is limited. With caustic blossom thinners, narrow effective application timings and concerns related to spring frost damage are barriers for commercial use in this region. If effective and safe, use of hormonal blossom thinners for apple would be an attractive alternative. We evaluated the effects and interactions of bloom thinners [6-benzyladenine (BA) and lime sulfur (LS, or calcium polysulfide) + stylet oil (LS+SO)] and a postbloom thinner (NAA) in the context of a multistep, carbaryl-free thinning program across three locations. Experiments were conducted in 2017 and 2018 on mature ‘Gala’ in North Carolina, Massachusetts, and Pennsylvania, USA. In four of six studies, BA at bloom increased the efficacy of postbloom NAA and reduced crop density ( P < 0.08). Postbloom NAA generally increased fruit relative growth rate (RGR) and reduced crop density. However, where NAA failed to reduce crop load, there was a negative influence on RGR. BA and LS+SO increased RGR in one of six studies; however, BA was generally ineffective as a blossom thinner, whereas LS+SO was more effective. Nevertheless, BA applied at bloom may have utility as part of a multistep thinning program. As a part of a multistep thinning program, BA applied at bloom may be useful in increasing efficacy of postbloom applications, particularly when use of caustic blossom thinners is not permitted.","PeriodicalId":13140,"journal":{"name":"Hortscience","volume":"227 8","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135112527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}